IN MILAN, IT'S SHORT OR LONG, SEXY OR SEDATE, FOR FALL

By BERNADINE MORRIS, Special to the New York Times

Published: March 10, 1987

MILAN, Italy, March 9—
Sparks are flying in all directions at the opening here of the Italian fashion shows for fall and winter. Instead of the sameness that usually marks the Milan presentations, there is a wide range of shapes and styles, and the daytime clothes are the most successful.

There is a choice of short and long hemlines, and short seems to be the winner. Narrow shoulders are making a significant entry alongside the aggressively padded styles that have dominated fashion for a decade.

New designers are attracting attention and excitement is in the air, tempered only by the drop in the value of the dollar, which makes everything more expensive. There are no bargains here, and the clothes shown this week will cost 20 to 30 percent more than last year's did when they arrive in stores in the United States in the fall.

Romeo Gigli, one of the newer designers, and Gianni Versace, one of the most popular, are defiantly showing higher-priced groups within their collections that have hand detailing and are being called couture. Stretch Yarns That Cling

Gigli is showing 14 of these styles privately and promises to make no more than 10 copies of each. They are in the spirit of his ready-to-wear designs. Slender jersey dresses are made with stretch yarns so that they cling to the body, and snug bodices are often paired with rounded skirts. Even the coats are made without shoulder pads, and sleeves long enough to cover the hands are one of his eccentric touches. The clothes in somber colors impart a waiflike look to the models.

The designs of Dolce & Gabbana have the same dreamy air. They cling to the body but, with a nod to the Japanese, have a lot of mobility. Jackets can be worn upside down or inside out. Skirts can be pulled high over the bosom or down to the hips. Some styles were covered with loops and buttons. By slipping a loop over a nearby button, a straight skirt converts to a draped one. Together with the Gigli styles, the clothes represent a new direction for Italian fashion.

Versace's styles are just the opposite in mood. They are flamboyant and outrageously sexy. He opened his collection with 30 so-called couture styles geared mostly to businesswomen. According to Versace, women who work wear a neatly tailored, rather long jacket in a fabric like chalk-striped worsted, a shirt and a gathered skirt that stops at midthigh. That a bank president might prefer to cover her knees does not interest the designer, who prefers short skirts for evening, too. Some of them have a pleated panel extending from the thigh to the floor. His metallic-mesh styles have lacy bra tops and sheer, embroidered net skirts: only the torso is opaque. Animal Motifs by Krizia

Of the styles by Mariuccia Mandelli for Krizia, the most acclaimed are knitted cashmere dresses cut along princess lines but fitted loosely to the body. With cowl necklines or hoods, they are soft and graceful for day. Gloves that have deep fur cuffs give them added punch. Shearling coats with reptile markings look smart, and sweaters with panda patterns are adorable. The panda is a felicitous addition to the continuing story of animal motifs in Krizia sweaters.

The amount of gold for evening is overwhelming. There are dresses of gold lace, crinkled and crushed lame and moire, and even gold leather jackets. Brown satin suits were a welcome relief from all this glitter.

Giorgio Armani is expanding his Emporio collection, which is half the price of his other styles. Jackets, for instance, range from $275 to $450. Emporio clothes have a clean-cut, collegiate look, like the early styles of Perry Ellis. Jackets have shaped waistlines and jodhpurs, shorts and knickers supplement knee- or calf-length skirts. A few coats have dropped shoulders and no pads. There are many more evening styles than in the past, and a number of them have pouffed skirts. Why? ''The young girls like them for evening,'' he said in French. ''Not me.''

The short full skirt has been acclaimed at two houses showing important collections. At Byblos the skirt, in black velvet or quilted silk, has a jaunty look for evening when it is paired with waist nippers and rounded boleros. The Byblos collection, by two British designers, Alan Cleaver and Keith Varty, has been gaining ground in recent seasons. This time the designers scored with short pleated skirts and cotton plaids, white shearling jackets decorated with inlays of black alpine flowers and skating skirts in blue denim or black wool.

Mario Valentino's design team, headed by Toshi Moon, has succeeded in giving his all-leather collection a snappy young look. The key is length: everything is short, from shearling coats flaring like skating skirts to beige suede dresses with a pouf around the hem.

Suede fitted coats, black patent-leather suits and bubble coats of Mongolian lamb all have a fresh new look. They give a lively dimension to leather fashions and also enlarge the scope of the Italian fashion scene. It is turning into a most exciting season.